1. Technical Field
The invention relates to hearing devices for communications and hearing aid applications. More particularly, the invention relates to hearing devices that are deeply inserted into the ear canal.
2. Description of the Prior Art
Technological advancements continue to reduce the size of hearing devices. This miniaturization is highly desirable for several reasons, including improved acoustics and cosmetic appeal. In hearing aids, for example, canal hearing devices that fit deeply into the ear canal are becoming increasingly popular. Canal devices are referred to as In-The-Canal (ITC) or Completely-In-the-Canal (CIC) depending on the depth of insertion. Alternatively, a hearing device may be an earpiece for audio and communications applications. Such hearing devices have also become considerably smaller and are being inserted more deeply into the ear canal.
Miniaturization of hearing devices presents substantial challenges to designers and users alike. Canal device designs must use the minimal available space to place components such as amplifiers, receivers (speakers), microphones, battery, controls, and wires with great efficiency. A design must also permit insertion and removal by the user with ease and accuracy. In view of the fact that the contours of the ear canal are narrow and bent (s-shaped), in sharp contrast to the simplified illustrations common in the literature, it is clear that inserting a device into the ear canal is quite challenging.
Handling and manipulating a hearing device during insertion or removal is especially problematic for those users who have limited dexterity. Hearing aid users, in general, tend to be elders who are likely to suffer from arthritis or neurological disorders affecting their motor function. These disorders, manifested by tremor, rigidity and irregular hand movements, make it difficult for many users to insert and remove a hearing aid properly. Improper insertion due to dexterity limitations not only leads to discomfort and cosmetic disadvantage, it also results in functional problems such as feedback. This phenomenon is manifested by an annoying whistling that occurs when acoustic leakages between a speaker and microphone are present. Therefore, feedback is likely to occur when a hearing device is not properly inserted into the ear canal.
Problems associated with insertion and removal of miniature hearing devices generally increase with the age of the individual wearer and also with increased miniaturization of the hearing device.
In the hearing aid industry, miniature canal devices are generally provided with a handle in the form of a strand that may be grasped with the fingertips to remove the device from the ear canal. The strand is typically attached permanently to the faceplate (the lateral end) of a hearing device. See, for example, Chasin, CIC Handbook, Chap. 10, pp. 180, Singular Publishing Group, Inc. (1997). The length, shape and texture of the strand handle is typically designed to minimize visibility to others while allowing maximum access and ease of handling by the user. To minimize the size of the hearing device, the strand handle is simply glued permanently to the hearing device during the manufacturing process.
Unfortunately, the features of a strand handle often require individual adjustments which cannot be anticipated prior to the custom fabrication process or the fitting. For example, a longer strand may be easier to handle for someone with dexterity limitations. However, a longer strand may be problematic for another due to anatomical interference from the pinna of the ear. Determining the correct physical features of the removal strand prior to the fitting process is not practical for many users in view of often conflicting requirements such as cosmetic appeal, usability, and the user's manual dexterity.
Because the handle is permanently attached, any modification or repair of a handle often requires returning the hearing aid to the manufacturer for retrofitting. This remake step not only delays the fitting process but also incurs additional expense for both the dispensing professional and the manufacturer, who typically offer liberal warranty policies to the end user.
Handle determination is further complicated by the fact that, post-fitting, a user may have different requirements after a learning process which may take several weeks. This may necessitate a subsequent retrofitting of a device which initially seemed well-suited for the user.
P. Van Vroenhoven, Hearing Aid Intended for Being Mounted Within the Ear Canal, U.S. Pat. No. 5,295,191 (Mar. 15, 1994) discloses a hearing aid with a dual function handle (extraction means 12) for extracting the hearing device and for conduction of infrared radiation into the hearing device. Similarly, J. Leenen, In the Ear Hearing Aid Having Extraction Tube Which Reduces Acoustic Feedback, U.S. Pat. No. 5,395,168 (Mar. 7, 1995) discloses a dual function handle for extracting a hearing device and for acoustically coupling sound into the hearing aid. A serious shortcoming of these devices is that the extraction element is fixed or fastened to the face-plate, thereby preventing the dispensing professional from selecting alternative handles which optimize ease of insertion and removal and cosmetic factors according to individual needs and preferences.
V. Giannetti, Hearing Aids of the Type Intended to be Fitted in the External Auditory Meatus of the User, U.S. Pat. No. 4,584,437 (Apr. 22, 1986) discloses a hearing device having a hinged battery cover such that the cover can be easily gripped by the user's fingers so that it can aid in positioning the aid in the user's ear. After insertion into the ear canal, the cover is then closed (FIG. 3, closed position), presumably for cosmetic reasons, during wearing. A major disadvantage of Giannetti is that considerable dexterity is required to lift the cover to the open position (FIG. 4) prior to removal of the miniature hearing aid from the ear.
M. Harada, Removal Handle for the Ear Hearing Aids, U.S. Pat. No. 4,565,904 (Jan. 21, 1986) also discloses a hinged handle with an enlarged end (bulbous end 30) for grasping with the fingers. One disadvantage of this device is that when the handle is in the closed position it is essentially flush with the face-plate making it difficult for persons with dexterity problems to open (FIG. 3) prior to grasping it to remove the deeply inserted hearing aid.
J. Carlson, Apparatus and Method for Manipulating Devices in Orifices, U.S. Pat. No. 5,003,608 (Mar. 26, 1991) discloses an apparatus and method for insertion and removal of a hearing device from the ear by using a similarly hinged handle which can swing out in response to a magnet placed near the handle, making it easy to grasp. One disadvantage of such an apparatus is that an external tool, a magnet, is required to pull the handle prior to grasping it. This is a serious inconvenience for users, particularly elders, who must remember to carry a magnet to insert and remove the hearing aid.
R. Claes and P. Van Vroenhoven, Hearing Aid With Pull-Out-String, Pull-Out String, and Method of Making a Hearing Aid, U.S. Pat. No. 5,381,484 (Jan. 10, 1995) disclose a removal strand with a plurality of beads at certain distances with respect to one another. Each bead can be severed to adjust the length of the strand according to the needs of the user. Claes et al. provide an advantage in terms of length adjustment. However, to select any other features such as grip size, texture or orientation requires the return of the hearing device to the manufacturer to replace the strand with a more suitable one.
It would be advantageous to provide a field selectable handle for hearing devices which meets the needs of the individual wearing the device. It would also be advantageous to provide a handle that is readily replaceable by the dispensing professional or by the user without requiring special tools, adhesives, or any labor intensive custom fabrication.